diff options
| author | Ingo Molnar <mingo@elte.hu> | 2008-01-30 15:34:09 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-01-30 15:34:09 +0300 |
| commit | ee01f1122ceb02a2c9b7142c5dd17b49e59ba774 (patch) | |
| tree | 82f4d23f6857e2cc8e623295d3b06ab70c05fa10 /arch | |
| parent | 1a4872529e13265d05ffae75b8d09697540016d2 (diff) | |
| download | linux-ee01f1122ceb02a2c9b7142c5dd17b49e59ba774.tar.xz | |
x86: init memory debugging
debug incorrect/late access to init memory, by permanently unmapping
the init memory ranges. Depends on CONFIG_DEBUG_PAGEALLOC=y.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/mm/init_32.c | 11 | ||||
| -rw-r--r-- | arch/x86/mm/init_64.c | 11 |
2 files changed, 22 insertions, 0 deletions
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index a72737c05747..8d7f723cfc28 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -783,6 +783,16 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end) { unsigned long addr; +#ifdef CONFIG_DEBUG_PAGEALLOC + /* + * If debugging page accesses then do not free this memory but + * mark them not present - any buggy init-section access will + * create a kernel page fault: + */ + printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n", + begin, PAGE_ALIGN(end)); + set_memory_np(begin, (end - begin) >> PAGE_SHIFT); +#else /* * We just marked the kernel text read only above, now that * we are going to free part of that, we need to make that @@ -798,6 +808,7 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end) totalram_pages++; } printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10); +#endif } void free_initmem(void) diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index f51180c02b8f..e0c1e98ad1bf 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -550,6 +550,16 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end) if (begin >= end) return; + /* + * If debugging page accesses then do not free this memory but + * mark them not present - any buggy init-section access will + * create a kernel page fault: + */ +#ifdef CONFIG_DEBUG_PAGEALLOC + printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n", + begin, PAGE_ALIGN(end)); + set_memory_np(begin, (end - begin) >> PAGE_SHIFT); +#else printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10); for (addr = begin; addr < end; addr += PAGE_SIZE) { ClearPageReserved(virt_to_page(addr)); @@ -575,6 +585,7 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end) set_memory_nx(begin, (end - begin)/PAGE_SIZE); } #endif +#endif } void free_initmem(void) |